As well known in the art, a mobile device refers to a kind of electronic device based on mobility and portability. With remarkable growths in related technologies, a great variety of mobile devices capable of supporting various end-user functions are increasingly popularized. Nowadays, such mobile devices may employ many input techniques. In particular, some mobile devices offer a touch-based input interface such as a touch screen that normally includes a touch panel and a display unit. The mobile device generates a touch event in response to a user's touch input made on the touch panel and performs a particular function based on the touch event.
In addition, the mobile device that includes the touch screen may often react to unintentional touches and consequently perform undesired functions. As such, most mobile devices provide a touch-lock function for the touch panel in order to prevent unwanted touch events from being generated. If the mobile device is in a touch semi-lock state, a user who desires to use a specific function should first cancel the touch semi-lock state. However, a process of cancelling the touch semi-lock state is somewhat complicated such that it may not be simply canceled in response to an unexpected action. In addition, because a process of activating a desired function is also complicated, a user may experience too much inconvenience.